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Table 2

Years before the frequency of a gene that confers a 10% advantagea to reach 0.50

Mode of inheritance

Initial frequency

No dominance

Dominant

Recessive

0.01

1,838

1,054

41,038

0.001

2,763

1,964

401,963

0.0001

3,684

2,884

4,002,884

aWe are assuming that favored genotype has a 10% advantage over the other genotypes; in the no dominance case, the relative fitness of the heterozygote is intermediate between that of the two homozygotes. With a 1% selective advantage, it would take 10 times as long for the gene to reach a frequency of 50%.

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